Any command execution fails

[marioarrigonineri]

Hi,
I cannot understand the correct set of commands I have to send to PX4 to takeoff.
I'm working on a local windows machine with PX4 and JMAV simulator.
Communication works fine, but I always receive a MAV_RESULT_FAILED.

Here is my simplest example:

	UdpConnector udp = new UdpConnector(InetAddress.getLocalHost(), 14570, 14550);
	final MavlinkConnection connection = MavlinkConnection.create(udp.getInputStream(), udp.getOutputStream());
	new Thread() {
		@Override
		public void run() {
			while (true) {
				try {
					connection.send1(255, 0,
							Heartbeat.builder().type(MavType.MAV_TYPE_GCS).autopilot(MavAutopilot.MAV_AUTOPILOT_PX4)
									.systemStatus(MavState.MAV_STATE_UNINIT).mavlinkVersion(1).build());
					Thread.sleep(1000);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		}
	}.start();
	connection.send1(255, 0, CommandInt.builder().command(MavCmd.MAV_CMD_COMPONENT_ARM_DISARM).param1(1).build());

	MavlinkMessage message;
	while ((message = connection.next()) != null) {
		Object p = message.getPayload();
		if (p instanceof Heartbeat || p instanceof CommandAck)
			System.out.println("" + message.getSequence() + " --> " + p);
	}

the output is:

67 --> CommandAck{command=EnumValue{value=400, entry=MAV_CMD_COMPONENT_ARM_DISARM}, result=EnumValue{value=4, entry=MAV_RESULT_FAILED}, progress=0, resultParam2=0, targetSystem=0, targetComponent=0}
176 --> Heartbeat{type=EnumValue{value=2, entry=MAV_TYPE_QUADROTOR}, autopilot=EnumValue{value=12, entry=MAV_AUTOPILOT_PX4}, baseMode=EnumValue{value=81, entry=null}, customMode=65536, systemStatus=EnumValue{value=3, entry=MAV_STATE_STANDBY}, mavlinkVersion=3}

cannot understand where is the problem.. is there any specific handshare or command sequence?

thanks

Mario

[benbarkay]

@marioarrigonineri have you tried using CommandLong instead?

Also, there could be different reasons for this to fail, like compass error or no gps fix etc, depending on the particular implementation of your autopilot.

[marioarrigonineri]

thank you..
As a first test I'm working with px4 toolchain on windows.. I guess someone already used it as a test environment.
I'll check further documentation, but I see few details. Cannot find any "sequence of commands from zero to takeff".
thanks for any support

[marioarrigonineri]

I tried using CommandLong.. same result :(

[benbarkay]

Are you printing out Statustext messages? These sometimes print out human readable messages when something's wrong, it might reveal the problem if the command is correct but the vehicle's state prevents from arming.

Also, I know in my tests with ardupilot firmware that I must first set mode to guided. This could be the problem if compass is calibrated and there's GPS 3D fix.

[benbarkay]

Also, the modes are set using the customMode portion of either SetMode or MAV_CMD_DO_SET_MODE depending on your firmware. So it's not as straightforward as setting the mode to something in MavMode, at least that is the case in ardupilot.

[benbarkay]

Closed for inactivity